**Opik Dashboard**:

- Added a new `created_by` column for each table to indicate who created the record
- Mask the API key in the user menu

**SDK**:

- Implement background batch sending of traces to speed up processing of trace creation requests
- Updated OpenAI integration to track cost of LLM calls
- Updated `prompt.format` method to raise an error when it is called with the wrong arguments
- Updated the `Opik` method so it accepts the `api_key` parameter as a positional argument
- Improved the prompt template for the `hallucination` metric
- Introduced a new `opik_check_tls_certificate` configuration option to disable the TLS certificate check.
